Specificity Of Smad Proteins In Transforming Growth Factor-beta Signaling
Funder
National Health and Medical Research Council
Funding Amount
$212,036.00
Summary
Transforming growth factor-betas (TGF-beta) regulate a fascinating array of cellular processes including cell proliferation, differentiation, migration, organization and death, as well as affect a wide range of biological functions, such as embryonic development, hematopoiesis and immune and inflammatory responses. Given the multifunctional nature of TGF-beta action, it is not surprising that the disruptions of TGF-beta functions have been implicated in many human disorders, particularly in colo ....Transforming growth factor-betas (TGF-beta) regulate a fascinating array of cellular processes including cell proliferation, differentiation, migration, organization and death, as well as affect a wide range of biological functions, such as embryonic development, hematopoiesis and immune and inflammatory responses. Given the multifunctional nature of TGF-beta action, it is not surprising that the disruptions of TGF-beta functions have been implicated in many human disorders, particularly in colorectal and pancreatic cancers. The Smad proteins (there are ten of them) are critical components of TGF-beta cellular actions. In fact, Smad4 also called DPC4 for deleted in pancreatic carcinoma locus 4. This project addresses how each Smad protein works at molecular level in the cell, and which part of biological functions it regulates. Collectively, the outcomes of the project may provide clear and specific molecular targets to treat TGF-beta related diseases such as colorectal and pancreatic cancers.Read moreRead less
Protein / Protein Interactions Important For AMP-activated Protein Kinase Regulation
Funder
National Health and Medical Research Council
Funding Amount
$242,545.00
Summary
The AMP-activated protein kinase (AMPK) is an enzyme that monitors the energy levels of the body. When oxygen and nutrient levels decrease, the energy levels of a cell also decrease leading to activation of the AMPK. This results in activation of energy-producing pathways and inhibition of energy-consuming pathways, allowing cells to match supply with demand to ensure their survival. The AMPK comprises of three proteins that together form a functional enzyme. In this application I aim to obtain ....The AMP-activated protein kinase (AMPK) is an enzyme that monitors the energy levels of the body. When oxygen and nutrient levels decrease, the energy levels of a cell also decrease leading to activation of the AMPK. This results in activation of energy-producing pathways and inhibition of energy-consuming pathways, allowing cells to match supply with demand to ensure their survival. The AMPK comprises of three proteins that together form a functional enzyme. In this application I aim to obtain a thorough understanding of the molecular basis of how the AMPK functions. I will determine how and where the three proteins interact with each other and determine where in a cell at any given time the AMPK can be found. This is an important question to answer because many proteins are inactive within the cytoplasm but when they are bound to the plasma membrane they are active. I have previously found the AMPK to be localized to the cytoplasm, membrane and nuclear compartments of the cell, but little is known about the AMPK s function in these different locations. Activation of the AMPK is known to depend on another protein that is also activated when cellular energy levels decrease. This protein has remained elusive to many researchers over the past few years. I plan to identify this protein using new bioinformatics together with the vast amount of information provided by the sequencing of the human genome. Exercise and reduced caloric intake activate the AMPK, these are associated with health benefits and reduce the risk of cardiovascular and neurodegenerative diseases, diabetes and obesity. For these reasons information on the role of the AMPK may improve our understanding of the reasons these diseases develop.Read moreRead less
Functional Characterization Of Caveolae And Caveolins
Funder
National Health and Medical Research Council
Funding Amount
$140,660.00
Summary
This project aims to study the cellular machinery that allows a cell to respond to its external environment. Specifically, this project focusses on the function of a family of membrane proteins, called caveolins, which are the major protein components of caveolae small pits which cover the surface of many mammalian cells. Caveolins are believed to regulate signalling from the external environment to the cell interior and loss of this regulation leads to uncontrolled growth leading to cancer. Sig ....This project aims to study the cellular machinery that allows a cell to respond to its external environment. Specifically, this project focusses on the function of a family of membrane proteins, called caveolins, which are the major protein components of caveolae small pits which cover the surface of many mammalian cells. Caveolins are believed to regulate signalling from the external environment to the cell interior and loss of this regulation leads to uncontrolled growth leading to cancer. Signalling from the cell surface relies on organisation of signalling components into modules. Our studies suggest that these modules are dependent on specific lipid molecules which form discrete patches, called lipid rafts, on the cell surface. We have hypothesised that caveolins control the lipid molecules associated with lipid rafts and so, indirectly, control signalling pathways. In particular, we have shown that caveolin is important in the regulation of cellular cholesterol, a vital molecule involved in maintaining the function of lipid raft domains. As numerous human diseases are associated with cholesterol imbalance, studies of caveolins can give fundamental new insights into this process, and the previously unidentified links between the cellular lipid balance and signal transduction. This project aims to use mutant caveolin molecules to disrupt caveolin function and so determine the role of caveolin in lipid regulation and in signal transduction. We will then use a lower vertebrate model system, which is amenable to experimental manipulation, to determine the role of caveolins and rafts in the development of the whole embryo.Read moreRead less
Molecular Mechanisms Underlying G Protein Coupled Receptor Signaling
Funder
National Health and Medical Research Council
Funding Amount
$596,956.00
Summary
The maintenance of optimum health and function of living cells, and consequently that of the whole organism, depends on how cells respond to a multitude of physical and chemical stimuli that continually bombard them. The majority of the chemical stimuli such as hormones and neurotransmitters impart their actions not by directly entering the cell, but instead, by binding to a specific receiver protein at the cell surface called a receptor. In one class of such receptors called G protein-coupled r ....The maintenance of optimum health and function of living cells, and consequently that of the whole organism, depends on how cells respond to a multitude of physical and chemical stimuli that continually bombard them. The majority of the chemical stimuli such as hormones and neurotransmitters impart their actions not by directly entering the cell, but instead, by binding to a specific receiver protein at the cell surface called a receptor. In one class of such receptors called G protein-coupled receptors, the transmission of the message to the interior of the cell involves yet another protein called G protein. These receptors are the most abundant type of cell surface receptors and form the targets for nearly 50% of currently used therapeutic drugs. It is, therefore, extremely important to unravel how each of these components works, and in particular to know how they work in living cells. This project utilizes state-of-the-art methodologies to examine interactions between receptors and their cognate G proteins, in living cells and in real-time. The work will answer fundamental questions about the nature of G protein-coupled receptor signaling and will aid in the future development of more effective therapeutic agents.Read moreRead less
Novel G-protein Coupled Receptor Interactions And Complexes With Distinct Function And Pharmacology
Funder
National Health and Medical Research Council
Funding Amount
$246,760.00
Summary
G protein coupled receptors (GPCRs) are the target in the human body for most of today's medicines. Almost all pharmaceutical companies market drugs that are GPCR agonists or antagonists aimed at diverse disease states. Our research is focused on the molecular basis of drug recognition and signalling by GPCRs. We use genetic engineering techniques to create new receptors and mutant receptors in order to identify the functional domains of these signalling molecules. We have recently established a ....G protein coupled receptors (GPCRs) are the target in the human body for most of today's medicines. Almost all pharmaceutical companies market drugs that are GPCR agonists or antagonists aimed at diverse disease states. Our research is focused on the molecular basis of drug recognition and signalling by GPCRs. We use genetic engineering techniques to create new receptors and mutant receptors in order to identify the functional domains of these signalling molecules. We have recently established a novel approach based on proximity-dependent fluorescent technologies to explore receptor interactions and have described the formation of functional G-protein coupled complexes in living cells. This project is to discover new receptor combinations which could potentially affect signalling pathways and redirect cellular responses. Investigation of the mechanisms involved in turning on and off the body s response to stimuli would provide valuable information for drug design and treatment of GPCR-related conditions. We have chosen to use two GPCRs as models for our study of the mechanisms controlling receptor driven cellular responses and the interactions between cellular components-proteins behind this control. Firstly, the gonadotropin releasing hormone receptor (GnRHR), a protein located in the pituitary which is pivotal in the control of reproduction and secondly, the thyrotropin releasing hormone receptor (TRHR), similarly located and involved in modulating thyroid and metabolic function. We will investigate the way these receptors interact with other cellular proteins in order for them to function. Ultimately this will provide a better understanding of how these clinically important proteins function and pave the way for the development of clinical applications that target these receptor systems, resulting in the effective treatment of a wide range of conditions and diseases, including pain, migraine, certain forms of cancer, neurological and reproductive disorders.Read moreRead less